Respuesta :
The event that extended that war was the French stopping the Germans from advancing in the west.
Answer:
The French stopped the German advance in the west.
Explanation:
The Western Front was the main theatre of war during the First World War. This describes the German invasions into Luxembourg and Belgium, and eventually France. After the French stopped the German advance in the West, the war became much longer and difficult to win. The Western Front also experienced a stalemate due to trench warfare.